428 



CHEMICAL DYNAMICS 



and then (the ferment having been destroyed by boiUng) evapo- 

 rated until precipitation (at room temperatm-es) just began. 

 The solution which was thus prepared contained the products of 

 the hydi'olysis of 400 grams of protamin and was free from un- 

 hydrolysed protamin, since the original solution (before evapo- 

 ration) was miscible with five volumes of acidulated alcohol 

 without any resulting opacity. To this solution were then added 

 300 cc. of a glycerin extract of the livers of the large soft-shelled 

 Cahfornia clam (Schizothcerus nuttalli), which contain a proteo- 

 lytic ferment of the trypsin type which is very resistant to auto- 

 destruction and therefore especially adapted for employment in 

 experiments of long duration. After the addition of this trypsin 

 the solution was still miscible with alcohol without cloudiness. 

 Excess of toluol was then added, and the flask (containing over 

 4 litres) was set aside at room temperature. 



The mixture gradually became opalescent, then cloudy, and, 

 finally, after the lapse of some months, a distinct precipitate 

 had formed. After five months the flask was opened, the con- 

 tents were heated to boiling to destroy the ferment, acidulated 

 with sulphuric acid, which dissolved the precipitate, and filtered. 

 Then four volumes of absolute alcohol were added, which resulted 

 in the throwing down of a heavy white precipitate, which, after 

 purification, was analysed. In all, about 2 grams were obtained. 



The percentage formula of the protamin sulphate employed 

 (salmin sulphate prepared from the spermatozoa of Roccus 

 lineatus) had previously been determined by Taylor and found 

 to be: 



C30H60N17O6.2 H2SO4. 



The analysis of the synthetical preparation yielded the following 

 results : 



The substance was digestible by trypsin and not digestible by 

 pepsin. Taylor concludes that it was salmin. A concentrated 



